Update 4/25/17 (by Liz MacDonald):
Steve has gone viral! Check out the articles here.
There’s a new dancing light display in the sky, and it’s not the usual aurora. We need your help to learn more!
Giving off a glow in mostly purple and green colors, the phenomenon was observed by members of a Facebook group called the “Alberta Aurora Chasers” who named the display “Steve.” Why Steve? Well, this is a reference to the popular children’s movie Over the Hedge where one of the characters isn’t sure what he is looking at and randomly names it Steve. Steve was formerly called by aurora chasers and photographers a “proton arc” (also known as a proton aurora). Proton aurora, or aurora caused by the raining down of protons from the magnetosphere is broad, diffuse, and dim visually unlike the structure of Steve that is narrow and has motion. So we know it is not a proton arc although we do not yet fully know what it is.
More than 50 observer reports have been seen in 2016 and we are hoping for more in 2017. We’re working with Canadian and European researchers, data providers, and the Ambassadors network on this and will bring you more information as we know more. Space scientists from NASA, the University of Calgary and other places are already trying to make Steve an acronym meaning “Strong Thermal Emission Velocity Enhancement” based on its characteristics from simultaneous satellite observations.
We are are still learning more about Steve, but here are seven things we think we know so far:
- Steve appears ~10-20° (in latitude) closer to the equator (south in the Northern hemisphere) than where the normal green aurora is overhead. This means it could be overhead at latitudes similar to Calgary, Canada.
- Steve is a very narrow arc aligned East-West and extending for hundreds or thousands of miles.
- Steve emits light in mostly purple-ish colors. It is quite faint but is usually photographed with 5-10 second exposures.
- Sometimes, it is accompanied by a rapidly evolving green short-lived picket fence structure.
- Steve can last 20 min or even longer.
- Steve appears to have a season. For instance, it has not been observed by citizen scientists from October 2016 to February 2017.
- This phenomena has been reported from the UK, Canada, Alaska, northern US states, and even New Zealand.
As we are still learning more about this unique phenomenon, reports from citizen scientists have been immensely helpful in tracking down the shape, location, and timing of Steve and giving clues to scientists about the origin of this mysterious piece of chemistry in the sky. Until then, keep submitting your observation to Aurorasaurus.org via the website or Aurorasaurus app.